The Weather Reports window lists reports in the order they were retrieved but if you need so, you can freely rearrange them.
To move a weather report to a different position, drag its header row in the list.
To reposition multiple weather reports, select their header rows and drag the selection to a new position.
To select reports that are next to each other (contiguous) in the list, press the Shift key and then click the first and last header row; to select reports that are not next to each other in the list, press the Command key and then click each header row.